Tried my hand at cutting and threading a barrel on a cheap gun, and didn't realize that my guide wasn't perfectly square. So my barrel is slanted on the end, and I crowned it before I realized my mistake. The cut is high on one side by about the width of one thread (as shown in the picture).



I presume that a suppressor is not a possibility at this point, but I'm wondering if this is something I can amend through sight adjustment, or if I'll have to get a gunsmith to cut it behind the threads if I want to hit anything.

If that is the muzzle end protruding from a slide, here's what I would do:

1) Remove barrel from gun and fixture in a strong holding device (vise).
2) Find or fabricate a bore guide that matches the land diameter of the rifling inside.
3) Using the bore guide as just that, take an flat end mill with cutting diameter larger than that of the OD of the barrel and face it to just above flush with the slide. This can be done by hand with the correct tools, lots of oil, and patience.
4) Then, using the same bore guide, use an 11° crowning cutter (or whatever crown you choose) to sink a crown.  Cut just enough to leave about half the wall thickness of the new face flat as flat. This can be done by hand with the correct tools, lots of oil, and patience.

See the photos in this thread:
Link

Thanks!